README.md

Privacy Preserving Distributed Hash Tables - Reality and Future

note: The current version of the paper is a draft and being review and
modified. This is an open research work: feel free to contribute with ideas,
corrections and content. This work is supported by hashmatter.

Abstract Distributed Hash Tables (DHT) are overlay networks that enable nodes to store and request data in a peer-to-peer (P2P) network. Data storage and data lookups are resolved collectively through a collaborative routing protocol, which makes storage location deterministic and data lookups possible. The collaborative nature of DHTs results on resilient, scalable and decentralized networks where nodes are not required to maintain a complete view of the network while, simultaneously, not relying on central authorities. These properties make DHTs an important building block for the decentralized web and P2P systems. However, the decentralized nature of DHTs introduces privacy vulnerabilities due to the metadata leaked during the routing and lookup protocols. In naïve DHT implementations, it is trivial for any adversary to gather information about which nodes are requesting what data and which nodes are providing what data, without being detected and with relative low resources. Nowadays, the decentralized web ecosystem is relying heavily on DHTs as networks such as IPFS and Dat are steadily reaching mainstream adoption. Thus, it is important to address privacy preserving vulnerabilities of DHTs. Failing to deliver on user privacy will render decentralized systems unattractive as a viable alternative to centralized systems. In this paper we review research on mechanisms and protocols to achieve privacy preserving DHTs, outline open problems and directions for future research.

The core of the paper is a literature review of research work on protocols and
mechanisms for enhancing privacy in DHTs and its vulnerabilities. Currently, the
literature section is organized as follow:

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